Sliding suture grasper

ABSTRACT

A device to assist in securing a holding a portion of a suture during an intra-abdominal suturing procedure, the device including an elongated tubular body, a handle, an inner member element, and a push button. The inner member element may include at least one grasping element that expands as the at least one grasping element is extended beyond a distal end of the elongated tubular. The device may include a proximal spring disposed within the push button and abutting against a proximal end of the inner member element to allow the at least one grasping element to retract into the elongated tubular body in a proximal direction.

CROSS-REFERENCE TO RELATED APPLICATION

This patent application is a continuation of U.S. patent applicationSer. No. 15/350,508 (filed Nov. 14, 2016 and issued as U.S. Pat. No.10,251,640), which is a continuation of U.S. patent application Ser. No.14/564,345 (filed Dec. 9, 2014 and issued as U.S. Pat. No. 9,492,163),which claims priority to U.S. Provisional Patent Application No.61/913,906 (filed Dec. 9, 2013), the disclosures of which areincorporated herein by reference in their entireties.

FIELD OF THE INVENTION

The present disclosure relates to tissue closure devices, moreparticularly to a suture grasper device for securing and holding aportion of a suture during an intraabdominal suturing procedure or thesuturing of a puncture wound generated by a surgical trocar or otherpuncturing devices.

BACKGROUND

Minimally invasive methods for conducting surgery on internal organs,tissues, ligaments and bones use extremely small instruments such ascatheters, laparoscopes, and the like. The instruments are introducedusing very small incisions, for example on the order of 5 mm to 18 mm indiameter, into which a trocar or other introducing device is placed. Thetrocars may have a diameter, for example, between 3 mm and 30 mm, withthe smaller trocars leaving the opening substantially unchanged. Thelarger trocars may enlarge the opening. The trocars provide a reliableand fixed opening for introducing and removing various surgicalinstruments, viewing devices and other instruments used during thesurgical procedure.

While the incisions and the trocar opening are quite small bytraditional surgical standards, they still require closure aftercompleting the surgical procedure. Surgical closure reduces thepossibility of post-surgical infection, postsurgical herniation (forexample in abdominal surgeries), subsequent bleeding or other effects.Closure can be accomplished either through manual suturing or suturinginstruments used to complete the closure. In either case, suturing ismade difficult by the small opening size, for example not only formanipulating the suture but also for visualizing the procedure. Closureis also made more difficult by the need to suture the subcutaneoustissue, for example fascial layers, separate from closure of theoverlying skin, and doing so through a very small opening in the skinwhile also avoiding possible injury or damage to the internal organsduring such a procedure.

Conventional closure techniques such as those for closing openings inthe abdominal wall pass sutures through the abdominal wall tissue adistance from the original trocar incision. One or more sutures are thentied off to close the subcutaneous layer followed by suitable closure ofthe skin layer. It has been noted that the distance of the suturelocation from the original incision opening is important in order tosecure a suitable amount of abdominal wall tissue for forming a reliableclosure. If the distance is too small, the closure may not be enough toreliably close the opening without later complications.

Tissue closure devices, for example laparoscopic port closure devices,may be introduced into the opening after removal of the trocar device tomake easier the suturing of the trocar opening. Various methods andstructures may help in closing the opening, but may require asignificant number of steps for completing the closure. Some devices mayrequire a significant amount of manual care in suturing the opening andtying off the suture, as well as close visualization for accomplishingthe closure. Additionally, some devices have a significant number ofcomponents or special devices in order to accomplish the closure, orthey may not provide consistent and reliable results even under normaloperating circumstances.

This disclosure relates to tissue closure devices, including surgicalsuturing devices as well as such devices that can be used forintra-abdominal suturing and suturing of puncture wounds generated bysurgical trocars and other puncturing devices.

SUMMARY

A sliding suture grasping device may be used to cross a tissue bed andretrieve a suture by initially capturing a portion of the suturedisposed within the body cavity and then facilitating free movement orsliding of the suture at or within the device tip during retraction ofthe device from the body cavity.

The sliding suture grasper may combine a needle with a means to retrievesuture from a template used to guide the insertion and retrievalprocedure. For example, the sliding suture grasper may be inserted intoan insertion point on the proximal portion of the template transverse tothe centerline of the template from an exit point on the template bodyto guide the grasper through the soft tissue and toward a suture portionretained by a distal part of the template for capture and retrieval ofthe suture portion. This retrieval maneuver could then be repeated on anopposite side of the template to facilitate retrieval of the other endof the suture on the opposite side of an opening in the tissue bed, forexample.

The suture grasper may comprise at least one element that can expandlaterally to encircle the suture and that is configured to allow sutureto slide freely after the suture has been captured.

The grasper may including a keying feature on the proximal handle thatinteracts with a keyway on the proximal end of the template. The key andkeyway could be configured such that the lateral expanding element isgenerally orthogonal to the suture to be captured held in the templatewhen the key resides in the keyway. The key/keyway feature could act asa stop and limit the penetration distance of the needle.

The suture grasper may be configured to automatically activate to expandwhen approaching the suture target and to deactivate or close whenretracting the retriever thereby capturing the suture during theretraction maneuver.

In one exemplary aspect, a suture grasper includes an elongated tubularbody defining an inner lumen, the elongated tubular body having aproximal end and a distal end. The suture grasper further includes ahandle attached to the proximal end of the elongated tubular element; aninner member element slidably disposed within the lumen of the elongatedtubular body, the inner member element having a proximal end configuredto slidably extend from and retract into the handle, and having a distalend configured with at least one grasping element; a push buttonextending from a proximal end of the handle, the push button beingcoupled to the inner member element for actuation or movement of theinner member element in a distal direction or a proximal direction. Thesuture grasper includes a proximal spring disposed within the pushbutton, the proximal spring abutting against the proximal end of theinner member element, to bias the inner member element distally. Thesuture grasper also includes an intermediate spring for biasing the pushbutton and the inner member element in the proximal direction. Thesuture grasper further includes a distal spring disposed between adistal end of the handle and a flanged proximal end of the elongatedtubular body, the push button including a distal end for contacting theflanged proximal end. In one aspect, actuation of the push button in thedistal direction beyond a predetermined point after compression of theintermediate spring causes the distal end of the push button to compressthe distal spring via the flanged proximal end, and the flanged proximalend transfers force to actuate the tubular body distally relative to theinner member element, to actuate and close the at least one graspingelement.

In one aspect, the at least one grasping element is configured to expandwider than the elongated tubular body.

In one aspect, the at least one grasping element includes at least twoexpandable arms.

In one aspect, the at least two expandable arms expand as the at leastone grasping element is extended beyond the distal end of the elongatedtubular body. The at least two expandable arms include a left arm and aright arm, the left arm and the right arm having a different hingepoint. The left arm and the right arm extend radially away at differentdistances.

In one aspect, the at least one grasping element includes at least twoexpandable arms, and the at least two expandable arms expand as the atleast one grasping element is extended beyond the distal end of theelongated tubular body.

In one aspect, the distal spring biases the push button and the innermember element in the proximal direction. The push button includes adetent end, and the distal spring biases the detent end to rest againstan inner proximal wall of the handle when the push button is in areleased position. The detent end of the push button compresses thedistal spring when the push button is depressed, and compression of thedistal spring transfers force to actuate the inner member element in thedistal direction.

In one aspect, a distal end of the push button compresses theintermediate spring when the push button is depressed, and compressionof the intermediate spring transfers force to actuate the inner memberelement in the distal direction.

In one aspect, the proximal end of the inner member element includes aside post, and the handle includes a stop element, the stop limitingtravel of the elongated tubular body in the proximal direction viaabutment with the flanged proximal end, and the stop element limitingtravel of the inner member element in the distal direction via abutmentwith the side post. The handle includes an inner proximal wall, theinner proximal wall limiting travel of the inner member element in theproximal direction via abutment with the side post.

In one aspect, the suture grasper further comprises a locking member toretain the push button in a predetermined axial location. The lockingmember extends laterally outward with respect to an axial direction ofthe push button.

In one aspect, the distal end of the elongated tubular body includes asharp tip capable of crossing or penetrating tissue. The sharp tip ofthe distal end of the elongated tubular body is beveled and configuredto cross or penetrate tissue. The at least one grasping element includesat least two expandable arms, and each of the at least two expandablearms have a different radius of curvature when expanding radially.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate various embodiments consistentwith the invention, and, together with the description, serve to explainthe principles of the invention.

FIG. 1 is a side sectional view of a sliding suture grasper, inaccordance with certain aspects of the present invention;

FIG. 2 is a side sectional view showing the sliding suture grasper ofFIG. 1 in a certain state of use, in accordance with certain aspects ofthe present invention;

FIG. 3 is a side sectional view showing the sliding suture grasper ofFIG. 1 in another state of use, in accordance with certain aspects ofthe present invention;

FIG. 4 is a side sectional view showing the sliding suture grasper ofFIG. 1 in another state of use including a captured portion of a suture,in accordance with certain aspects of the present invention;

FIG. 5 is a side sectional view of a sliding suture grasper, inaccordance with other aspects of the present invention;

FIG. 6 is a side sectional view showing the sliding suture grasper ofFIG. 5 in a certain state of use, in accordance with certain aspects ofthe present invention;

FIG. 7 is a side sectional view showing the sliding suture grasper ofFIG. 5 in another state of use, in accordance with certain aspects ofthe present invention;

FIG. 8 is a side sectional view showing the sliding suture grasper ofFIG. 5 in another state of use including a captured portion of a suture,in accordance with certain aspects of the present invention.

FIG. 9 is a side view of a sliding suture grasper, in accordance withother aspects of the present invention;

FIG. 10 is a front sectional view of the sliding suture grasper of FIG.9 at A-A.

FIG. 11 is a front view of a sliding suture grasper in accordance withcertain aspects of the present disclosure in a certain state of use; and

FIG. 12 is a front view of a sliding suture grasper in accordance withcertain aspects of the present disclosure in another state of use.

DETAILED DESCRIPTION

The invention will now be described with reference to the drawingfigures, in which like reference numerals refer to like partsthroughout.

Various aspects of a sliding suture grasping device may be illustratedby describing components that are coupled, attached, and/or joinedtogether. As used herein, the terms “coupled”, “attached”, and/or“joined” are used to indicate either a direct connection between twocomponents or, where appropriate, an indirect connection to one anotherthrough intervening or intermediate components. In contrast, when acomponent is referred to as being “directly coupled”, “directlyattached”, and/or “directly joined” to another component, there are nointervening elements present.

Relative terms such as “lower” or “bottom” and “upper” or “top” may beused herein to describe one element's relationship to another elementillustrated in the drawings. It will be understood that relative termsare intended to encompass different orientations of a sliding suturegrasping device in addition to the orientation depicted in the drawings.By way of example, if aspects of a sliding suture grasping device shownin the drawings are turned over, elements described as being on the“bottom” side of the other elements would then be oriented on the “top”side of the other elements. The term “bottom” can therefore encompassboth an orientation of “bottom” and “top” depending on the particularorientation of the apparatus.

As shown in FIGS. 1-4, a sliding suture grasper device 100 is comprisedof an elongated tubular body 110 having a proximal end 112 and a distalend 114. The distal end 114 may be beveled to provide a sharp tip 116capable of crossing or penetrating tissue. Within the lumen of theelongated tubular body 110 resides an inner member element 120 having aproximal end 122 and distal end 124 that is free to move along thelength of the elongated tubular body 110. The elongated tubular body 110may be attached to a handle 130 such that the proximal end 122 of theinner member element 120 may slidably extend from and retract into thehandle 130. The distal end 124 of the inner member element 120 maycomprise at least one grasping element 140 that expands wider than theelongated tubular body 110 diameter when the grasping element 140 isextended distal of the elongated tubular body 110. The proximal end 122of the inner member element 120 rests against a proximal spring 150 thatresides within a push button 160. The push button 160 resides within theproximal end of the handle 130 and can be actuated by pushing in thedistal direction to advance the inner member element 120 distallyallowing the grasping element 140 to expand. Within the handle 130 anddistal to the push button 160 resides a distal spring 170 that biasesthe push button 160 in the proximal direction against the proximal endof the handle 130 and also biases the inner member element 120 in theproximal direction.

As shown in FIG. 2, during use, the grasper device 100 may be insertedinto a tissue bed. When doing so, the inner member element 120 may bepushed proximally due to tissue resistance thereby compressing theproximal spring 150 much like a traditional Veress needle. In thismanner, the grasping element 140 may be configured with at least twoexpandable arms 142 (see FIG. 3) that form a bulbous, rounded distal endwhen not in the expanded grasping position. The grasping element 140 maythus provide a degree of safety against an accidental poke from thesharp tip 116 by providing a rounded distal end Which extends beyond thesharp tip 116, as shown in FIG. 1. The inner member element 120 may bepushed proximally until the grasping element 140 no longer extendsbeyond the distal tip 116, allowing the distal tip 116 to penetrate thetissue bed.

As the distal tip 116 of the device exits the tissue into a body cavity,for example, the pressure against the grasping element 140 is relievedand the inner member element 120 returns to its resting state wherein adetent end 162 of the push button 160 rests against a proximal wall 132of the handle 130, as shown in FIG. 1. The device 100 may thus bepositioned in proximity to a portion of suture 180 to be captured.

As shown in FIG. 3, with the device 100 thus positioned near the suture180, the push button 160 may then be depressed to compress the distalspring 170 with the detent end 162 of the push button 160. Thecompression of the distal spring 170 in turn transfers force to theinner member element 120 to thereby actuate the inner member element 120in the distal direction. The expandable arms 142 of the grasping element140, which may be spring actuated by being comprised of a suitablematerial formed to maintain a certain shape, may expand upon beingreleased from the distal end 114 of the elongated tubular body 110. Asshown in FIG. 4, upon release of the push button 160, the distal spring170 drives the push button 160 proximally until the detent end 162 ofthe push button 160 seats against the proximal wall 132 of the handle130. As the distal spring 170 drives the push button 160 proximally, theinner member 120 may be actuated in the proximal direction causing theexpandable arms 142 to close around the suture portion 180. At thistime, the at least one grasping element 140 has captured and secured theportion of suture 180 in its proximity within or near the distal tip 116of the device 100. The grasping element 140 is configured to secure thesuture portion 180 in a manner that allows it to slide freely throughthe grasping element 140 upon retraction of the device 100 from the bodycavity.

FIGS. 5-8 illustrate a sliding suture grasper device 200 in accordancewith yet other aspects of the present disclosure. The device 200 may beused to cross a tissue bed and retrieve a suture by initially capturinga portion of the suture disposed within a body cavity and thenfacilitating free movement or sliding of the suture at or within thedevice tip during retraction of the device from the body cavity. Thesliding grasper device 200 employs a means to position nearby thesuture, expand or open a grasping element 140 about the suture, and thencapture and retain the suture as part of a continuous action of a pushbutton system.

As shown in FIGS. 5-8, the grasper device 200 may comprise an elongatedtubular body 210 having a proximal end 212 and distal end 214, an innermember element 220 having a proximal end 222, a distal end 224, andfeaturing a grasping element 240 at its distal end 224, a handle 230, aproximal spring 250, a mid spring 255, a push button 260, and a distalspring 270. The elongated tubular body 210 includes a distal end 214beveled to provide a sharp tip 216 capable of crossing or penetratingtissue. The proximal end 212 of the elongated tubular body 210 may beflanged and/or configured for slidably mounting within a distal portion232 of the handle 230. The elongate tubular body 210 is free to move apredetermined distance within the distal portion 230 of the handle 230and has a stroke that is limited by the interaction of the proximal end212 with features within the handle 230, such as a stop element 234.

The elongate tubular body 210 may be biased in the proximal direction byinclusion of the distal spring 270 positioned between the proximal end222 of the elongate tubular body 210 and the handle 230. Within thelumen of the elongated tubular body 210 slidably resides the innermember element 220 having proximal end 222 and distal end 224, the innermember element 220 being free to move along the longitudinal length ofthe elongated tubular body 210. The proximal end 222 of the inner memberelement 220 may also be flanged and include a side post 223 distal tothe flanged end 222. The flanged proximal end 222 of the inner memberelement 220 maintains and secures the inner member element 220 withinthe inner core of the push button 260.

The distal end of the inner member element comprises at least onegrasping element 240 that may include one or more expandable arms 242,for example. The expandable arms 242 of the grasping element 240 may bespring actuated by being comprised of a suitable material formed tomaintain a certain shape, and may be configured to expand upon beingreleased from the distal end 214 of the elongated tubular body 210. Theexpandable arms 242 may expand wider than a diameter of the elongatedtubular body 210 when the grasping element 240 is extended distal to thedistal end 214 of the tubular body 210. Because the distal end 214 ofthe tubular body 210 may be beveled, in accordance with aspects of thepresent disclosure, each arm 242 of the grasping element 240 may have adifferent radius of curvature to prevent one arm from expanding radiallyfurther due to the different distances each arm 242 will extend from thebeveled end 214. For example, in a configuration wherein the arms 242 donot share a common hinge point, a left arm and a right arm will extendradially away different distances due to one arm having a cantileveredlength that is greater than the cantilevered length of the second armdue to an effective hinge point formed by the beveled end 214 beingdifferent for the first arm than the second arm. By having a differentradius of curvature, for example, permits both arms 242 to openapproximately symmetrically about a longitudinal centerline of thedevice 200.

The proximal spring 250 is situated proximal to the flanged end 222 ofthe inner element and within the inner core of the push button 260 as ameans to bias the inner member element 220 towards the distal end of thepush button 260. The proximal spring 250 may comprise a single spring ofa known constant spring rate, a single spring with variable spring ratesalong its length, or multiple springs with varying spring rates. Thesemultiple springs could be preferably arranged in tandem versus coaxialor parallel. The side post 223 on the inner member element 220 limitsthe longitudinal movement or stroke of the inner member in both theproximal and distal directions within the handle 230. For example, theside post 223 may be formed to abut against a proximal end 236 of thehandle 230 at one limiting end of the inner member stroke and to abutagainst the same stop element 234 formed to seat the proximal end 212 ofthe elongated tubular body 210. In accordance with other aspects of thepresent disclosure, the stop element 234 may be separated into multipledetents for limiting the separate strokes of the elongated tubularmember 210 and the inner member element 220.

The mid spring 255 may be configured to seat against an extended distalend 262 of the push button 260 and bias the push button 260 in theproximal direction. The push button 260 may thus be positioned against apush button detent 238 configured into the proximal wall 236 of thehandle 230 when the mid spring 255 is extended. A distal end 256 of themid spring 255 may seat against an inner flange 237 configured into thestop 234 or any suitable portion of the handle 230 that is isolated fromthe elongate tubular body 210 and distal spring 270.

The push button 260 resides within the proximal end of the handle 230and is actuated by pushing in the distal direction to advance the innermember element 220 distally which allows the grasping element 240 toexpand. The push button 260 may include side openings or slots designedto allow unconstrained, longitudinal movement of the side post 223 ofthe inner member element 220.

In use, as shown in FIGS. 5-8, the device 200 may first be introducedinto a template for guiding the device 200 in a predetermined directiontoward a tissue bed. As shown in FIG. 5, when the device 200 is insertedinto the tissue bed, the inner member element 220 may be pushedproximally due to tissue resistance on the bulbous, rounded end of thegrasping element 240 formed when the two arms 242 are compressed in aclamping fashion toward each other. As the inner member element 220 ispushed proximally, the proximal spring 250 may be compressed and/or themid spring 255 may be stretched such that the inner member element 220retracts into the elongated tubular body 210 to expose the sharp,beveled tip 216 for penetration through the tissue bed, much like atraditional Veress needle. As the distal tip 216 of the device 200 thenexits the tissue bed into the body cavity, the resistance is relievedand the inner member element 220 returns to its resting state. The depthof penetration may be limited by the interference of the handle 230 witha proximal portion of the template thereby positioning the distal end ofthe device 200 above and in close proximity to a portion of suture 280to be captured. The push button 260 is then actuated to sequentiallycompress the proximal springs 250, the mid spring 255 and finally thedistal spring 270.

As shown in FIGS. 6 and 7, actuation of the push button 260 in thedistal direction initially moves the inner member element 220 distallyuntil the side post 223 abuts against the stop 234 configured into thehandle 230. At this point, the expandable arms 242 of the grasperelement 240 may extend beyond the distal end 214 of the tubular body 210such that the arms 242 are extended toward and opened radially aroundthe suture portion 280. With the side post 223 abutting the stop 234,the inner member element 220 is prevented from any further longitudinalmovement in the distal direction with respect to the handle 230.

Rather, as shown in FIG. 8, continued actuation of the push button 260forces the distal end 262 of the push button 260 to abut the flangedproximal end 212 of the elongated tubular body 210. The proximal spring250, the mid spring 255, and the distal spring 270 are all compressed asthe distal end 262 of the push button 260 pushes the elongated tubularbody 210 distally. As the distal end 214 of the tubular member 210slides over the expanded arms 242 of the grasping element 240, theexpanded arms 242 are forced to close around the suture portion 280 inorder to slidably capture the suture. The push button 260 could be heldmanually by the surgeon or alternatively may comprise a locking feature,as will be described in detail below, to maintain the security ofgrasping element 240 in a closed position with the suture secured in asliding embrace therein. The device 200 would then be withdrawn outsideof the body cavity until the end of the suture completely exits thedevice 200. Upon release of the push button 260 and/or lock, the varioussprings would return to their extended positions and be ready for thenext suture retrieval maneuver.

FIGS. 9-12 illustrate a sliding suture grasper device 300 in accordancewith yet another aspect of the present disclosure. The device 300 maycomprise an elongated tubular body 310 having a proximal end 312 anddistal end 314, and an inner member element 320 having a proximal end322 and a distal end 324, the distal end 324 featuring a graspingelement 340. In one aspect, the device 300 may include a handle 330, aproximal spring 350, a mid spring 355, a distal spring 360, and a pushbutton 370. In one aspect, the push button 370 may include a lockingmember 375, which may be biased to extend laterally outward with respectto an axial direction of the push button 370. In one aspect, the handle330 may include an opening 335 to secure the locking member 375 suchthat the push button 370 is retained at a predetermined axial location.In one aspect, securing the push button 370 at the predetermined axiallocation maintains the grasping element 340 in a closed position with asuture secured in a sliding embrace therein.

It will be appreciated that the foregoing description provides examplesof the disclosed system and technique. However, it is contemplated thatother implementations of the disclosure may differ in detail from theforegoing examples. All references to the disclosure or examples thereofare intended to reference the particular example being discussed at thatpoint and are not intended to imply any limitation as to the scope ofthe disclosure more generally. All language of distinction anddisparagement with respect to certain features is intended to indicate alack of preference for those features, but not to exclude such from thescope of the disclosure entirely unless otherwise indicated.

Recitation of ranges of values herein are merely intended to serve as ashorthand method of referring individually to each separate valuefalling within the range, unless otherwise indicated herein, and eachseparate value is incorporated into the specification as if it wereindividually recited herein. All methods described herein can beperformed in any suitable order unless otherwise indicated herein orotherwise clearly contradicted by context.

What is claimed is:
 1. An instrument comprising: an elongated bodydefining a lumen, the elongated body having a proximal portion and adistal portion; a handle attached to the proximal portion of theelongated body; an inner member slidably disposed within the lumen ofthe elongated body, the inner member having a distal end effector; apush button extending from a proximal portion of the handle, the pushbutton configured to actuate or move the inner member; a first springdisposed between a portion of the push button and a portion of the innermember, the first spring being configured to bias the inner member in adistal direction; and a second spring configured to bias the push buttonand the inner member in a proximal direction.
 2. The instrument of claim1, wherein the first spring is configured to compress when the distalend effector is pushed into the elongated body, and the second spring isconfigured to compress when the push button is pushed distally toadvance the distal end effector out of the elongated body.
 3. Theinstrument of claim 1, wherein the second spring engages the pushbutton.
 4. The instrument of claim 3, wherein the second spring engagesa distal portion of the push button.
 5. The instrument of claim 1,wherein the second spring is disposed around the inner member.
 6. Theinstrument of claim 1, wherein the second spring biases the push buttonagainst a proximal portion of the handle.
 7. The instrument of claim 1,wherein the first spring is disposed in the push button.
 8. Theinstrument of claim 1, wherein the distal end effector includes at leastone grasping element.
 9. The instrument of claim 8, wherein the at leastone grasping element is configured to expand when in an extendedconfiguration beyond the distal portion of the elongated body.
 10. Theinstrument of claim 9, wherein the at least one grasping elementincludes at least two expandable arms.
 11. The instrument of claim 1,wherein the distal end effector has a round distal portion when in aretracted configuration.
 12. The instrument of claim 1, wherein thedistal portion of the elongated body includes a sharp tip.
 13. Theinstrument of claim 1, wherein the first spring engages the push button.14. The instrument of claim 1, wherein the push button has a detentportion that rests against a proximal wall of the handle in a restingstate.
 15. The instrument of claim 1, wherein a proximal portion of theinner member is received in the push button.
 16. The instrument of claim1, further comprising a stop element, wherein the second spring extendsbetween the stop element and the portion of the push button.
 17. Theinstrument of claim 1, further comprising a third spring configured tobias the elongated body in the proximal direction, wherein the thirdspring extends between a flange of the elongated body and a distalportion of the handle.
 18. The instrument of claim 1, wherein the pushbutton has a locking member, and the handle has an opening configured tosecure the locking member and to retain the push button in apredetermined axial location.
 19. The instrument of claim 18, whereinthe locking member extends from the push button in a lateral directionwith respect to an axial direction of the push button.
 20. Theinstrument of claim 19, wherein the locking member is biased in thelateral direction.